This invention relates generally to a method of manufacturing a water treatment device, remanufacturing a water treatment device, and a water treatment device made according to such methods. More particularly, the invention relates to a method of manufacturing and remanufacturing a water treatment device having a media bed in a housing made from a length of open pipe, a pair of end caps secured one to each opening of the pipe, a pair of screens at each open end of the pipe outwardly of the media, and fittings penetrating each end cap outwardly of the associated screen.
Water is often treated by passing it through a bed of suitable media. This may be a cation exchange resin, such as that used to soften hard water by exchanging sodium ions for calcium and magnesium ions present in the water. The media may alternatively be a granular-activated carbon for the removal of chlorine and other volatile organic compounds from drinking water. One common form of housing used to contain the media is made from a cut length of extruded plastic pipe, such as PVC, with end caps permanently attached over the open ends. Restraining disks are fitted within the end caps on support members over the openings in order to retain the media, but pass water. This approach provides for an inexpensive housing which is especially useful for media volumes ranging from approximately 50 cubic inches up to approximately 300 cubic inches. The restraining disks are typically made from a pad of filtering materials, such as porous plastic sold under the trademark Porex, or a fine mesh screen or a combination of these. Inlet and outlet fittings are inserted in the end caps outwardly of the restraining disks. Such inlet and outlet fittings may be attached by drilling and tapping the housing and then screwing in standard male pipe fittings to which tubing, or the like, may be attached.
Such known water treatment devices are made by first fixing one end cap which supports one restraining disk to an open end of the pipe typically by using an adhesive, such as a solvent glue. The treatment media is then added into the pipe and the other end cap and restraining disk are fixed in place using similar techniques.
One disadvantage of this known technique is that solvent glues are cured in the presence of the treatment media. As the solvent adhesive dries, organic fumes are given off which can be absorbed by the treatment media. The organic substances may then be released back into the water during initial use of the treatment device. This may, at least temporarily, decrease rather than increase the quality of the water consumed.
A second disadvantage of known devices is that the treatment media cannot be replaced. Such treatment media has a limited life and must be discarded when spent. Once the media is spent, the known treatment devices must be discarded in their entirety. This results in non-degradable plastic containers being dumped in landfills, even though the housing is still in excellent condition.
The present invention provides a method of manufacturing a water treatment device which allows media to be replaced after it has been spent. The present invention further provides a method for remanufacturing a water treatment device in order to replace the spent media. The invention further provides a water treatment device that is made according to such methods.